我有多个网络摄像头连接到我的电脑,我想根据它们的信息(名称、分辨率等)选择其中一个摄像头。是否有一种方法可以列出计算机上所有可用的摄像头,而不是尝试在cv2.VideoCapture()中使用所有索引?
我有多个网络摄像头连接到我的电脑,我想根据它们的信息(名称、分辨率等)选择其中一个摄像头。是否有一种方法可以列出计算机上所有可用的摄像头,而不是尝试在cv2.VideoCapture()中使用所有索引?
import cv2
def list_ports():
"""
Test the ports and returns a tuple with the available ports
and the ones that are working.
"""
is_working = True
dev_port = 0
working_ports = []
available_ports = []
while is_working:
camera = cv2.VideoCapture(dev_port)
if not camera.isOpened():
is_working = False
print("Port %s is not working." %dev_port)
else:
is_reading, img = camera.read()
w = camera.get(3)
h = camera.get(4)
if is_reading:
print("Port %s is working and reads images (%s x %s)" %(dev_port,h,w))
working_ports.append(dev_port)
else:
print("Port %s for camera ( %s x %s) is present but does not reads." %(dev_port,h,w))
available_ports.append(dev_port)
dev_port +=1
return available_ports,working_ports
这个方案在你的代码中实现起来很容易。
正如 @ketza 所指出的,有些情况下工作端口不是连续的,这个版本将在退出 while 循环之前测试至少 5 个不工作的端口:
import cv2
def list_ports():
"""
Test the ports and returns a tuple with the available ports and the ones that are working.
"""
non_working_ports = []
dev_port = 0
working_ports = []
available_ports = []
while len(non_working_ports) < 6: # if there are more than 5 non working ports stop the testing.
camera = cv2.VideoCapture(dev_port)
if not camera.isOpened():
non_working_ports.append(dev_port)
print("Port %s is not working." %dev_port)
else:
is_reading, img = camera.read()
w = camera.get(3)
h = camera.get(4)
if is_reading:
print("Port %s is working and reads images (%s x %s)" %(dev_port,h,w))
working_ports.append(dev_port)
else:
print("Port %s for camera ( %s x %s) is present but does not reads." %(dev_port,h,w))
available_ports.append(dev_port)
dev_port +=1
return available_ports,working_ports,non_working_ports
if ( cameraNum < 0 || devices.count <= NSUInteger(cameraNum) ) {
fprintf(stderr, "OpenCV: out device of bound (0-%ld): %d\n", devices.count-1, cameraNum);
[localpool drain];
return 0;
}
devices.count
返回可用设备的数量,但OpenCV没有将其返回给用户的方法。if ((unsigned)m_deviceID >= m_devices.Get()->Size)
{
OutputDebugStringA("Video::initGrabber - no video device found\n");
return false;
}
再次强调,没有函数可以将m_devices.Get()->Size
返回给用户。Linux代码有点复杂。
如果您正在从代码构建OpenCV,则可以添加一个返回可用设备数量的函数。或者更好的是,向OpenCV提交拉取请求并附上您的补丁。
首先安装包:
pip install pygrabber==0.1
代码 #
from pygrabber.dshow_graph import FilterGraph
graph = FilterGraph()
print(graph.get_input_devices())# list of camera device
try:
device =graph.get_input_devices().index("name camera that I want to use it ")
except ValueError as e:
device = graph.get_input_devices().index("Integrated Webcam")#use default camera if the name of the camera that I want to use is not in my list
vid=cv2.VideoCapture(device)